XPS and XRD study of photoconductive CdS films obtained by a chemical bath deposition process

Cadmium sulfide layers have been obtained from CdCl2, CS(NH2)2, NH4Cl, NH3 and H2O solutions using the chemical bath deposition technique at 50 °C. After dipping in a solution of 0.7 mass% CdCl2 in CH3OH and thermal treatment under Ar at 400 °C for 30 min, the CdS layers obtained acquire a photosensitivity amounting to a ratio, between photocurrent values in the light and in the dark, of four orders of magnitude. The chemical changes of the layers occurring, as evidenced by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), during their preparation in solution and after thermal treatment are discussed.